MulDiv

// KERNEL32.dll
#include <windows.h>

INT MulDiv(
    INT nNumber,
    INT nNumerator,
    INT nDenominator
);

<DllImport("KERNEL32.dll", ExactSpelling:=True)>
Public Shared Function MulDiv(
    nNumber As Integer,   ' INT
    nNumerator As Integer,   ' INT
    nDenominator As Integer   ' INT
) As Integer
End Function

' nNumber : INT
' nNumerator : INT
' nDenominator : INT
Declare PtrSafe Function MulDiv Lib "kernel32" ( _
    ByVal nNumber As Long, _
    ByVal nNumerator As Long, _
    ByVal nDenominator As Long) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

MulDiv = ctypes.windll.kernel32.MulDiv
MulDiv.restype = ctypes.c_int
MulDiv.argtypes = [
    ctypes.c_int,  # nNumber : INT
    ctypes.c_int,  # nNumerator : INT
    ctypes.c_int,  # nDenominator : INT
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('KERNEL32.dll')
MulDiv = Fiddle::Function.new(
  lib['MulDiv'],
  [
    Fiddle::TYPE_INT,  # nNumber : INT
    Fiddle::TYPE_INT,  # nNumerator : INT
    Fiddle::TYPE_INT,  # nDenominator : INT
  ],
  Fiddle::TYPE_INT)

#[link(name = "kernel32")]
extern "system" {
    fn MulDiv(
        nNumber: i32,  // INT
        nNumerator: i32,  // INT
        nDenominator: i32  // INT
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("KERNEL32.dll")]
public static extern int MulDiv(int nNumber, int nNumerator, int nDenominator);
"@
$api = Add-Type -MemberDefinition $sig -Name 'KERNEL32_MulDiv' -Namespace Win32 -PassThru
# $api::MulDiv(nNumber, nNumerator, nDenominator)

#uselib "KERNEL32.dll"
#func global MulDiv "MulDiv" sptr, sptr, sptr
; MulDiv nNumber, nNumerator, nDenominator   ; 戻り値は stat
; nNumber : INT -> "sptr"
; nNumerator : INT -> "sptr"
; nDenominator : INT -> "sptr"
; ※HSP3.7は #func のため戻り値はシステム変数 stat に格納されます。

#uselib "KERNEL32.dll"
#cfunc global MulDiv "MulDiv" int, int, int
; res = MulDiv(nNumber, nNumerator, nDenominator)
; nNumber : INT -> "int"
; nNumerator : INT -> "int"
; nDenominator : INT -> "int"

; INT MulDiv(INT nNumber, INT nNumerator, INT nDenominator)
#uselib "KERNEL32.dll"
#cfunc global MulDiv "MulDiv" int, int, int
; res = MulDiv(nNumber, nNumerator, nDenominator)
; nNumber : INT -> "int"
; nNumerator : INT -> "int"
; nDenominator : INT -> "int"

import (
	"golang.org/x/sys/windows"
	"unsafe"
)

var (
	kernel32 = windows.NewLazySystemDLL("KERNEL32.dll")
	procMulDiv = kernel32.NewProc("MulDiv")
)

// nNumber (INT), nNumerator (INT), nDenominator (INT)
r1, _, err := procMulDiv.Call(
	uintptr(nNumber),
	uintptr(nNumerator),
	uintptr(nDenominator),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // INT

function MulDiv(
  nNumber: Integer;   // INT
  nNumerator: Integer;   // INT
  nDenominator: Integer   // INT
): Integer; stdcall;
  external 'KERNEL32.dll' name 'MulDiv';

result := DllCall("KERNEL32\MulDiv"
    , "Int", nNumber   ; INT
    , "Int", nNumerator   ; INT
    , "Int", nDenominator   ; INT
    , "Int")   ; return: INT

●MulDiv(nNumber, nNumerator, nDenominator) = DLL("KERNEL32.dll", "int MulDiv(int, int, int)")
# 呼び出し: MulDiv(nNumber, nNumerator, nDenominator)
# nNumber : INT -> "int"
# nNumerator : INT -> "int"
# nDenominator : INT -> "int"
# なでしこ1は32bit・ANSI(Shift_JIS)。文字列=char*(ANSI)、ポインタ/ハンドル=void*(4byte)。